Customizing Business Catalyst default javascript alerts with jGrowl

BC-Alerts-and-jGrowl.js

// Default BC alert messages
/*
var Oshoplang = {
    RemoveError: 'ERROR: To remove or update quantities select the View Cart link.',
    Added: '  item(s) added to your cart.',
    OutOfStock: 'Either product is out of stock or choose a smaller quantity',
    PreOrder: ' item(s) pre-ordered and added to your cart.',
    MinLimit: 'ERROR: Quantity entered is too small, please enter a larger quantity.',
    MaxLimit: 'ERROR: Quantity entered is too large, please enter a smaller quantity.',
    InvalidQuantity: 'ERROR: Quantity entered is not valid.',
    CartEmpty: 'Your Shopping cart is empty.',
    CartUpdateSuccess: 'Shopping cart updated successfully.',
    InvalidShip: 'ERROR: Please choose a valid shipping option.',
    ChooseState: 'ERROR: Please choose a destination state to calculate state tax.',
    EnterZip: 'ERROR: Please enter in your Zip/Postcode to calculate shipping costs for your order.',
    ChooseShip: 'ERROR: Please select a shipping charge for your order.',
    IncorrectGForm: 'ERROR: Your gift voucher form is not setup correctly. Please reset to original to restore.',
    EnterGName: 'ERROR: Please enter a name for the recipient of your gift voucher.',
    InvalidGEmail: 'ERROR: Please enter a valid email address for the recipient of your gift voucher.',
    EnterGMessage: 'ERROR: Please enter a personal message for the recipient of your gift voucher.',
    ChooseAttribute: 'ERROR: Please choose relevant options before adding to cart.'
};
*/

// Customize BC alerts with jGrowl
// Also requires nl2br function below
// https://github.com/stanlemon/jGrowl
window.alert = function(msg) {
	switch(msg) {
    case 'ERROR: Please choose relevant options before adding to cart.':
		var newMsg = '<b>Hang on!</b> Please select at least one flavor...';
        $.jGrowl(nl2br(newMsg));
		break;
	case 'ERROR: Please choose a valid shipping option.':
		var newMsg = '<b>Wait!</b> How do you want this shipped?';
        $.jGrowl(nl2br(newMsg));
		break;
	default:
		$.jGrowl(nl2br(msg));
	}
}

// Convert line breaks for jGrowl display, or other stuff
// Reference: http://stackoverflow.com/questions/2919337/jquery-convert-line-breaks-to-br-nl2br-equivalent
function nl2br(str, is_xhtml) {   
	var breakTag = (is_xhtml || typeof is_xhtml === 'undefined') ? '<br />' : '<br>';    
	return (str + '').replace(/([^>\r\n]?)(\r\n|\n\r|\r|\n)/g, '$1'+ breakTag +'$2');
}